Nanostructuration of soft hydrogels: synthesis and characterization of saccharidic methacrylate gels

With the tremendous development of biosensors, there is a strong need in new biocompatible materials avoiding possible denaturing of biological species, which can be easily processed with already existing technologies. The scope of this study was to develop new hydrogels which could be nanostructured by common lithographic methods. Therefore, new methacrylate hydrogels are described, which include functionalized monomers bearing either neutral groups, such as saccharidic moieties, anionic, or cationic groups. The gels have been synthesized by redox or photochemical-initiated radical polymerization. Their porosity has been characterized by thermoporometry, AFM, and electronic microscopy. The kinetics of the photocross-linking has been analyzed by piezorheometry on some of the materials and has been shown to be compatible with technological process time range. Although the obtained hydrogels are soft, their nanostructuration into 500-nm patterns could be performed by nanoimprint photolithography process, and these patterns were observed to be stable for several months.